The disclosure relates to ink-based digital printing. In particular, the disclosure relates to printing variable data directly onto a print substrate that may be smooth and non-absorbent using an ink-based digital printing system that includes dampening fluid and ink.
Ink-based digital printing uses a variable data lithography printing system, or digital offset printing system. A “variable data lithography system” is a system that is configured for lithographic printing using high viscosity lithographic inks and based on digital image data, which may be variable from one image to the next. “Variable data lithography printing,” or “digital ink-based printing,” or “digital offset printing” is lithographic printing of variable image data for producing images on a substrate that are changeable with each subsequent rendering of an image on the substrate in an image forming process.
The problem of printing high viscosity inks or materials using variable data is a current problem for current marking systems. Current systems such as offset lithography and inkjet marking can either print high viscosity inks or variable data but not both. In conventional offset printing, the printing process may include transferring radiation-curable ink onto a portion of an imaging member surface (plate, drum, or the like) that has been selectively coated with a dampening fluid layer according to invariant image data. The ink is then transferred from the printing plate to a print substrate such as paper, plastic, or metal on which an image is being printed and subsequently cured. However, while conventional offset printing can print medium to high viscosity inks it cannot print variable data. Inkjet marking systems can print variable data but not using medium or high viscosity inks. Further, a digital system containing a blanket or plate will have difficulties providing cleaning systems capable of reliably and safely removing residual ink from a reimageable surface of the blanket or plate without affecting its longevity. These challenges need to be met in order for variable data lithography printing systems to work efficiently for a wide range of paper media and inks.
As such, there is a need to overcome the deficiencies of conventional printing technology for printing variable data with a wide range of inks and print substrates. There is also a need in the art for a printing process that can print inks of various viscosities directly to the print substrate with variable image data.